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1.
Ann Intensive Care ; 14(1): 65, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658426

RESUMO

BACKGROUND: During the first COVID-19 pandemic wave, COVID-19-associated pulmonary aspergillosis (CAPA) has been reported in up to 11-28% of critically ill COVID-19 patients and associated with increased mortality. As new SARS-CoV-2 variants emerged, the characteristics of critically ill COVID-19 patients have evolved, particularly in the era of Omicron. The purpose of this study is to investigate the characteristics of CAPA in the era of new variants. METHODS: This is a prospective multicenter observational cohort study conducted in France in 36 participating intensive care units (ICU), between December 7th, 2021 and April 26th 2023. Diagnosis criteria of CAPA relied on European Confederation of Medical Mycology (ECMM)/International Society for Human & Animal Mycology (ISHAM) consensus criteria. RESULTS: 566 patients were included over the study period. The prevalence of CAPA was 5.1% [95% CI 3.4-7.3], and rose to 9.1% among patients who required invasive mechanical ventilation (IMV). Univariable analysis showed that CAPA patients were more frequently immunosuppressed and required more frequently IMV support, vasopressors and renal replacement therapy during ICU stay than non-CAPA patients. SAPS II score at ICU admission, immunosuppression, and a SARS-CoV-2 Delta variant were independently associated with CAPA in multivariable logistic regression analysis. Although CAPA was not significantly associated with day-28 mortality, patients with CAPA experienced a longer duration of mechanical ventilation and ICU stay. CONCLUSION: This study contributes valuable insights into the prevalence, characteristics, and outcomes of CAPA in the era of Delta and Omicron variants. We report a lower prevalence of CAPA (5.1%) among critically-ill COVID-19 patients than previously reported, mainly affecting intubated-patients. Duration of mechanical ventilation and ICU stay were significantly longer in CAPA patients.

2.
Intensive Care Med Exp ; 11(1): 48, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37544942

RESUMO

BACKGROUND: Despite current broad natural and vaccine-induced protection, a substantial number of patients infected with emerging SARS-CoV-2 variants (e.g., BF.7 and BQ.1.1) still experience severe COVID-19. Real-life studies investigating the impact of these variants on clinical outcomes of severe cases are currently not available. We performed a prospective multicenter observational cohort study. Adult patients with acute respiratory failure admitted between December 7, 2021 and December 15, 2022, in one of the 20 participating intensive care units (17 from the Greater Paris area and 3 from the North of France) were eligible for inclusion if they had SARS-CoV-2 infection confirmed by a positive reverse transcriptase-polymerase chain reaction (RT-PCR). Full-length SARS-CoV-2 genomes from all included patients were sequenced by means of next-generation sequencing. The primary endpoint of the study was day-28 mortality. RESULTS: The study included 158 patients infected with three groups of Omicron sublineages, including (i) BA.2 variants and their early sublineages referred as "BA.2" (n = 50), (ii) early BA.4 and BA.5 sublineages (including BA.5.1 and BA.5.2, n = 61) referred as "BA.4/BA.5", and (iii) recent emerging BA.5 sublineages (including BQ.1, BQ.1.1, BF.7, BE.1 and CE.1, n = 47) referred as "BQ.1.1". The clinical phenotype of BQ1.1-infected patients compared to earlier BA.2 and BA.4/BA.5 sublineages, showed more frequent obesity and less frequent immunosuppression. There was no significant difference between Omicron sublineage groups regarding the severity of the disease at ICU admission, need for organ failure support during ICU stay, nor day 28 mortality (21.7%, n = 10/47 in BQ.1.1 group vs 26.7%, n = 16/61 in BA.4/BA.5 vs 22.0%, n = 11/50 in BA.2, p = 0.791). No significant relationship was found between any SARS-CoV-2 substitution and/or deletion on the one hand and survival on the other hand over hospital follow-up. CONCLUSIONS: Critically-ill patients with Omicron BQ.1.1 infection showed a different clinical phenotype than other patients infected with earlier Omicron sublineage but no day-28 mortality difference.

3.
Infect Dis Now ; 53(7): 104737, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37331699

RESUMO

OBJECTIVES: In this era of bacterial resistance, avoiding inappropriate use of antibiotic treatments is of major importance. Respiratory tract infections are frequent among older patients, and differentiating viral from bacterial infections is a challenge. The aim of our study was to evaluate the impact of recently available respiratory PCR testing on antimicrobial prescription in geriatric acute care. METHODS: We performed a retrospective study, including all hospitalized geriatric patients who had had multiplex respiratory PCR testing prescribed from 1st October 2018 to 30th September 2019. The PCR test comprised a respiratory viral panel (RVP) and a respiratory bacterial panel (RBP). PCR testing could be prescribed at any time during hospitalization by geriatricians. Our primary endpoint was antibiotic prescription after viral multiplex PCR testing results. RESULTS: All in all, 193 patients were included, 88 (45.6%) of whom had positive RVP, while none had positive RBP. Patients with positive RVP had significantly fewer antibiotic prescriptions following test results than patients with negative RVP (odds ratio (OR) 0.41, 95% confidence interval (CI) 0.22-0.77; p = 0.004). Among positive-RVP patients, factors associated with antibiotic continuation were presence of radiological infiltrate (OR 12.02, 95%CI 3.07-30.29), and detected Respiratory Syncytial Virus (OR 7.54, 95%CI 1.74-32.65). That said, discontinuation of antibiotic treatment seems safe. CONCLUSION: In this population, the impact of viral detection by respiratory multiplex PCR on antibiotic therapy was low. It could be optimized by means of clearly formulated local guidelines, qualified staff and specific training by infectious disease specialists. Cost-effectiveness studies are necessary.

4.
Diagnostics (Basel) ; 13(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37371009

RESUMO

INTRODUCTION: Prior to the emergence of COVID-19, when influenza was the predominant cause of viral respiratory tract infections (VRTIs), this study aimed to analyze the distinct biological abnormalities associated with influenza in outpatient settings. METHODS: A multicenter retrospective study was conducted among outpatients, with the majority seeking consultation at the emergency department, who tested positive for VRTIs using RT-PCR between 2016 and 2018. Patient characteristics were compared between influenza (A and B types) and non-influenza viruses, and predictors of influenza were identified using two different models focusing on absolute eosinopenia (0/mm3) and lymphocyte count <800/mm3. RESULTS: Among 590 VRTIs, 116 (19.7%) were identified as outpatients, including 88 cases of influenza. Multivariable logistic regression analysis revealed the following predictors of influenza: in the first model, winter season (adjusted odds ratio [aOR] 7.1, 95% confidence interval [CI] 1.12-45.08) and absolute eosinopenia (aOR 6.16, 95% CI 1.14-33.24); in the second model, winter season (aOR 9.08, 95% CI 1.49-55.40) and lymphocyte count <800/mm3 (aOR 7.37, 95% CI 1.86-29.20). Absolute eosinopenia exhibited the highest specificity and positive predictive value (92% and 92.3%, respectively). CONCLUSION: During the winter season, specific biological abnormalities can aid physicians in identifying influenza cases and guide the appropriate use of antiviral therapy when rapid molecular tests are not readily available.

5.
Int J Infect Dis ; 130: 205-207, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36948447

RESUMO

We present the case of an 81-year-old man, who was immunocompetent, who was admitted to the hospital with symptoms of fever and dyspnea suspected to be caused by COVID-19. Further examination revealed a triple coinfection, as determined by multiplex polymerase chain reaction testing, caused by the respiratory syncytial virus, human coronavirus OC43, and rhinovirus. Upon auscultation, diffuse wheezing without crackles was detected. After ruling out the possibility of acute heart failure with pulmonary edema, the patient was treated with nebulization of terbutaline for a period of 72 hours. This case serves to demonstrate the potential dangers of lifting barrier measures, such as mandatory face masks in high-risk areas, during the fall-winter season. In addition, it highlights the challenges that may arise in the post-COVID-19 era because reliance on flu vaccinations alone may not be sufficient.


Assuntos
COVID-19 , Coinfecção , Coronavirus Humano OC43 , Infecções por Enterovirus , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Vírus , Masculino , Humanos , Idoso de 80 Anos ou mais , Rhinovirus , Coinfecção/diagnóstico
7.
Nat Commun ; 13(1): 6025, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224216

RESUMO

Infection with SARS-CoV-2 variant Omicron is considered to be less severe than infection with variant Delta, with rarer occurrence of severe disease requiring intensive care. Little information is available on comorbid factors, clinical conditions and specific viral mutational patterns associated with the severity of variant Omicron infection. In this multicenter prospective cohort study, patients consecutively admitted for severe COVID-19 in 20 intensive care units in France between December 7th 2021 and May 1st 2022 were included. Among 259 patients, we show that the clinical phenotype of patients infected with variant Omicron (n = 148) is different from that in those infected with variant Delta (n = 111). We observe no significant relationship between Delta and Omicron variant lineages/sublineages and 28-day mortality (adjusted odds ratio [95% confidence interval] = 0.68 [0.35-1.32]; p = 0.253). Among Omicron-infected patients, 43.2% are immunocompromised, most of whom have received two doses of vaccine or more (85.9%) but display a poor humoral response to vaccination. The mortality rate of immunocompromised patients infected with variant Omicron is significantly higher than that of non-immunocompromised patients (46.9% vs 26.2%; p = 0.009). In patients infected with variant Omicron, there is no association between specific sublineages (BA.1/BA.1.1 (n = 109) and BA.2 (n = 21)) or any viral genome polymorphisms/mutational profile and 28-day mortality.


Assuntos
COVID-19 , SARS-CoV-2 , Estado Terminal , Humanos , Fenótipo , Estudos Prospectivos , SARS-CoV-2/genética
8.
PLoS Pathog ; 18(7): e1010619, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35797399

RESUMO

Respiratory syncytial virus (RSV) is the primary cause of severe respiratory infection in infants worldwide. Replication of RSV genomic RNA occurs in cytoplasmic inclusions generating viral ribonucleoprotein complexes (vRNPs). vRNPs then reach assembly and budding sites at the plasma membrane. However, mechanisms ensuring vRNPs transportation are unknown. We generated a recombinant RSV harboring fluorescent RNPs allowing us to visualize moving vRNPs in living infected cells and developed an automated imaging pipeline to characterize the movements of vRNPs at a high throughput. Automatic tracking of vRNPs revealed that around 10% of the RNPs exhibit fast and directed motion compatible with transport along the microtubules. Visualization of vRNPs moving along labeled microtubules and restriction of their movements by microtubule depolymerization further support microtubules involvement in vRNPs trafficking. Approximately 30% of vRNPs colocalize with Rab11a protein, a marker of the endosome recycling (ER) pathway and we observed vRNPs and Rab11-labeled vesicles moving together. Transient inhibition of Rab11a expression significantly reduces vRNPs movements demonstrating Rab11 involvement in RNPs trafficking. Finally, Rab11a is specifically immunoprecipitated with vRNPs in infected cells suggesting an interaction between Rab11 and the vRNPs. Altogether, our results strongly suggest that RSV RNPs move on microtubules by hijacking the ER pathway.


Assuntos
Vírus Sincicial Respiratório Humano , Ribonucleoproteínas , Proteínas rab de Ligação ao GTP , Endossomos/metabolismo , Humanos , Microtúbulos/metabolismo , Transporte Proteico/fisiologia , Vírus Sincicial Respiratório Humano/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas Virais/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
9.
Int J Infect Dis ; 119: 217-224, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35405349

RESUMO

BACKGROUND: Following a study of predictors of superinfection in viral respiratory tract infections (VRTIs), this study analyzes the predictors of the outcome. METHODS: Multicenter retrospective study conducted among adults who tested positive for VRTIs with reverse-transcription polymerase chain reaction. We compared characteristics between influenza virus, Paramyxoviridae, and Pneumoviridae and identified predictors of favorable short-term outcome, admission to the intensive care unit (ICU), and mortality. RESULTS: A total of 590 patients had VRTI, including 347 (59%) influenza infections. Mean (SD) patient age was 71.0 (18.3) years, with a sex ratio of 0.91. In multivariate analyses, predictors of favorable short-term outcome were age ≤75 years (adjusted odds ratio [aOR] 5.38 [95% confidence interval, 1.59-18.2]), absence of respiratory disease (4.94 [1.01-24.37]), and absence of superinfection (aOR 3.91 [1.37-11.13]). The predictors of ICU admission were age ≤75 years (aOR 3.28 [1.71-6.25]), chronic respiratory disease (aOR 2.49 [1.20-5.19]), and procalcitonin level >0.25 ng/mL (aOR 4.25 [1.55-11.67]). Predictors of mortality were use of inhaled corticosteroids (2.49 [1.10-5.63]), influenza infection (2.73 [1.27-5.85]), Charlson score ≥5 (5.35 [1.90-15.05]), superinfection (2.54 [1.05-6.18]), and eosinophil count <50/µL (4.39 [1.19-16.2]). Certainty of superinfection was significantly associated with mortality (2.23 [1.15-4.3]). CONCLUSION: Our study revealed that superinfection was significantly related to the outcome, and that virus species affects mortality. These findings emphasize the need for improving the tools used in daily practice to confirm certainty of superinfection and for broader implementation of vaccination of individuals at risk of VRTIs.


Assuntos
Influenza Humana , Infecções Respiratórias , Superinfecção , Viroses , Adulto , Idoso , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Paris , Estudos Retrospectivos , Estações do Ano , Superinfecção/epidemiologia , Viroses/epidemiologia
11.
J Infect Dis ; 226(6): 1027-1035, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34636898

RESUMO

BACKGROUND: Viral respiratory tract infections (VRTIs) are among the most common diseases, but the risks of superinfection for different virus species have never been compared. METHODS: Multicenter retrospective study conducted among adults who tested positive for VRTIs with reverse-transcription polymerase chain reaction. We compared characteristics between influenza (A or B) and paramyxoviruses (respiratory syncytial virus, parainfluenza virus types 1 and 3, and human metapneumovirus) and identified predictors of superinfection and hospitalization.s. RESULTS: Five hundred ninety patients had VRTI, including 347 (59%) influenza and 243 paramyxovirus infections with comparable rates of superinfections (53% vs 60%). In multivariate analyses, the predictors of superinfections were age >75 years (adjusted odds ratio, 2.37 [95% confidence interval, 1.65-3.40]), chronic respiratory disease (1.79 [1.20-2.67]), and biological abnormalities, including neutrophil count >7000/µL (1.98 [1.34-2.91)], eosinophil count <50/µL (2.53 [1.61-3.98], and procalcitonin level >0.25ng/mL (2.8 [1.65-4.73]). The predictors of hospitalization were age >75 years old (adjusted odds ratio, 3.49 [95% confidence interval, 2.17-5.63]), paramyxovirus infection (2.28 [1.39-3.75]), long-term use of inhaled corticosteroids (2.49 [1.13-5.49]), and biological abnormalities, including neutrophil count >7000/µL (2.38 [1.37-4.12)] and procalcitonin level >0.25ng/mL (2.49 [1.23-5.02]). Kaplan-Meier survival curves showed that influenza-infected patients had a higher mortality rate than those with paramyxovirus infections (8.9% vs 4.5%, respectively; P = .02). CONCLUSIONS: Our study revealed a high rate of superinfection (56%), not related to viral species. However influenza virus was associated with a poorer prognosis than paramyxoviruses, pleading for a broader and large-scale vaccination of individual at risk of VRTIs.


Assuntos
Influenza Humana , Infecções por Paramyxoviridae , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Superinfecção , Adulto , Idoso , Hospitalização , Humanos , Infecções por Paramyxoviridae/epidemiologia , Pró-Calcitonina , Estudos Retrospectivos , Superinfecção/epidemiologia
15.
Eur J Clin Microbiol Infect Dis ; 40(10): 2235-2241, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33782783

RESUMO

We report evaluation of 30 assays' (17 rapid tests (RDTs) and 13 automated/manual ELISA/CLIA assay (IAs)) clinical performances with 2594 sera collected from symptomatic patients with positive SARS-CoV-2 rRT-PCR on a respiratory sample, and 1996 pre-epidemic serum samples expected to be negative. Only 4 RDT and 3 IAs fitted both specificity (> 98%) and sensitivity (> 90%) criteria according to French recommendations. Serology may offer valuable information during COVID-19 pandemic, but inconsistent performances observed among the 30 commercial assays evaluated, which underlines the importance of independent evaluation before clinical implementation.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/sangue , Imunoensaio/métodos , SARS-CoV-2/imunologia , COVID-19/virologia , Humanos , Imunoensaio/economia , Imunoglobulina M/sangue , Kit de Reagentes para Diagnóstico , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
16.
BMC Geriatr ; 21(1): 120, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579210

RESUMO

BACKGROUND: Acquired infections in hospitalized elderly people are a growing concern. In long-term care facilities with multiple staff and visitor contacts, virus outbreaks are a common challenge for infection prevention teams. Although several studies have reported nosocomial RSV outbreaks in long term care facilities, molecular epidemiology data are scarce. METHODS: RSV RNA was detected in respiratory samples from 19 patients in a long-term care hospital for elderly in Paris in March 2019 over a 3 weeks period. Genotyping was performed using nucleotide sequencing. Sociodemographic and clinical characteristics of cases part of a unique cluster, were retrospectively reviewed. RESULTS: Molecular investigation of theses RSV cases, revealed a unique cluster of 12 nosocomial cases in 2 adjacent wards. Mean age of these outbreak's cases was 89. All patients had underlying medical conditions. Seven exhibited lower respiratory symptoms and three experienced decompensation of underlying chronic heart condition. Two patients died. CONCLUSIONS: This case report highlights the importance of RSV in causing substantial disease in elderly in case of nosocomial outbreak and the contributions of molecular epidemiology in investigation and management of such outbreak.


Assuntos
Infecção Hospitalar , Infecções por Vírus Respiratório Sincicial , Idoso , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Hospitais , Humanos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/epidemiologia , Estudos Retrospectivos
17.
Open Forum Infect Dis ; 7(11): ofaa394, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33204745

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of a current pandemic worldwide. This virus can reach all organs and disturbs the immune system, leading to a cytokine storm in severe forms. We aimed to report cutaneous features among coronavirus disease 2019 (COVID-19) hospitalized patients. METHODS: We performed a cross-sectional study on 1 given day among all patients hospitalized in acute care for COVID-19 and included all patients with cutaneous features. Follow-up 48 hours later was obtained. RESULTS: Among 59 adult patients hospitalized on the day of the study in an infectious diseases ward for SARS-CoV-2 infection who were confirmed by molecular assay and/or radiological findings (computed tomography scan), 40 were included. Several cutaneous manifestations were found: macular exanthema (80%), face edema (32%), livedo (13%), urticarial rash (8%), purpura (5%), oral lichenoid lesions (33%), and conjunctivitis (18%). Cutaneous biopsy was performed in 17 patients. Histological findings showed mast cell hyperplasia (100%), superficial perivascular infiltrate of lymphocytes (94%), and superficial edema (47%) consistent with capillary leak. CONCLUSIONS: Various dermatological signs can be encountered during COVID-19. A macular rash was the most frequent. All cutaneous features could be related to a vascular leak process.

18.
Clin Kidney J ; 13(6): 1101-1104, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33391755

RESUMO

BACKGROUND: The objectives were to characterize Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease 2019 (COVID-19) in patients with acute kidney injury (AKI). METHODS: Kidney biopsy samples in two Caucasian patients and one African with COVID-19 AKI were investigated. RESULTS: All patients had a high-level non-selective glomerular proteinuria. SARS-CoV-2 samples by real-time polymerase chain reaction (RT- PCR) assay were all-negative, as well as for virus particles in the kidney by electron microscopy. The three patients and patients with other AKI did not differ significantly with regard to angiotensin-converting enzyme 2 and transmembrane protease serine 2 kidney staining. CONCLUSIONS: The kidney damage particularly in Caucasians in COVID-19 seems to be an AKI, possibly by the systemic inflammatory response.

19.
Sci Rep ; 9(1): 15258, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31649314

RESUMO

Human respiratory syncytial virus (RSV) is a globally prevalent negative-stranded RNA virus, which can cause life-threatening respiratory infections in young children, elderly people and immunocompromised patients. Its transcription termination factor M2-1 plays an essential role in viral transcription, but the mechanisms underpinning its function are still unclear. We investigated the cellular interactome of M2-1 using green fluorescent protein (GFP)-trap immunoprecipitation on RSV infected cells coupled with mass spectrometry analysis. We identified 137 potential cellular partners of M2-1, among which many proteins associated with mRNA metabolism, and particularly mRNA maturation, translation and stabilization. Among these, the cytoplasmic polyA-binding protein 1 (PABPC1), a candidate with a major role in both translation and mRNA stabilization, was confirmed to interact with M2-1 using protein complementation assay and specific immunoprecipitation. PABPC1 was also shown to colocalize with M2-1 from its accumulation in inclusion bodies associated granules (IBAGs) to its liberation in the cytoplasm. Altogether, these results strongly suggest that M2-1 interacts with viral mRNA and mRNA metabolism factors from transcription to translation, and imply that M2-1 may have an additional role in the fate of viral mRNA downstream of transcription.


Assuntos
Mapas de Interação de Proteínas/fisiologia , RNA Viral/metabolismo , Vírus Sincicial Respiratório Humano/metabolismo , Proteínas Virais/metabolismo , Humanos , Infecções por Vírus Respiratório Sincicial/virologia
20.
J Vis Exp ; (146)2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-31009004

RESUMO

The use of recombinant viruses has become crucial in basic or applied virology. Reverse genetics has been proven to be an extremely powerful technology, both to decipher viral replication mechanisms and to study antivirals or provide development platform for vaccines. The construction and manipulation of a reverse genetic system for a negative-strand RNA virus such as a respiratory syncytial virus (RSV), however, remains delicate and requires special know-how. The RSV genome is a single-strand, negative-sense RNA of about 15 kb that serves as a template for both viral RNA replication and transcription. Our reverse genetics system uses a cDNA copy of the human RSV long strain genome (HRSV). This cDNA, as well as cDNAs encoding viral proteins of the polymerase complex (L, P, N, and M2-1), are placed in individual expression vectors under T7 polymerase control sequences. The transfection of these elements in BSR-T7/5 cells, which stably express T7 polymerase, allows the cytoplasmic replication and transcription of the recombinant RSV, giving rise to genetically modified virions. A new RSV, which is present at the cell surface and in the culture supernatant of BSRT7/5, is gathered to infect human HEp-2 cells for viral amplification. Two or three rounds of amplification are needed to obtain viral stocks containing 1 x 106 to 1 x 107 plaque-forming units (PFU)/mL. Methods for the optimal harvesting, freezing, and titration of viral stocks are described here in detail. We illustrate the protocol presented here by creating two recombinant viruses respectively expressing free green fluorescent protein (GFP) (RSV-GFP) or viral M2-1 fused to GFP (RSV-M2-1-GFP). We show how to use RSV-GFP to quantify RSV replication and the RSV-M2-1-GFP to visualize viral structures, as well as viral protein dynamics in live cells, by using video microscopy techniques.


Assuntos
DNA Recombinante/genética , Engenharia Genética/métodos , Vírus Sincicial Respiratório Humano/genética , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico , Vírus Sincicial Respiratório Humano/fisiologia , Transcrição Gênica , Transfecção , Replicação Viral
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